The Computer and Informatics Resource Center (CIRC) serves the computational needs of Cancer Center researchers. Today, data for clinical and basic science studies are collected, managed and analyzed electronically. Results are then reported using a variety of software tools; the final publication is often available on-line. This information infrastructure is vital to the success of cancer research. To support this infrastructure, the CIRC staff provides expertise in both computer system and informatics. They maintain operating systems, application software, and Internet connectivity, develop and manage databases and Web services, and provide reference materials and education to end users. The emphasis of the CIRC has dramatically shifted during the last funding period from a computation-driven facility to an Internet-based informatics center.